<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script src="../../vuejs/vue.js"></script>
<div id="app">
    <ul class="pagination">
        <li v-for="n in pageCount">
            <a href="javascripit:void(0)" v-bind:class="activeNumber === n + 1 ? 'active' : ''">{{ n + 1 }}</a>
        </li>
    </ul>
</div>
</body>

<script>
    var vm = new Vue({
        el: '#app',
        data: {
            activeNumber: 5,
            pageCount: 10
        }
    })
</script>
<style>
    .active{
        color: aqua;
        background-color: blueviolet;
    }
</style>
</html>